Synthesis of enantiopure 5.7-spirodiamines: (S)-1,7-diaza[4.6]undecane and related compounds
摘要:
The efficient synthesis of enantiomerically pure (S)-1,7-diaza[4.6]undecane and (S)-7-methyl-1,7-diaza[4.6]undecane and related compounds is reported. These novel diamines are obtained from (S)-proline, which is reacted with chloral to give an enantiomerically pure oxazolidinone, which is alkylated at the alpha-position using cis-1,4-clibromobutene. The resulting allylbromide is then reacted with ammonia or methylamine to yield, as intermediates, allylamines, which ring close to give the corresponding spirolactams. The parent and the 7-methyl (S)-5.7-spirodiamines are obtained via reduction in two steps of the spirolactams. The expected absolute configuration was confirmed by X-ray structural analysis. Enantiomeric excess (> 99.8% ee) was determined using the Mosher amides of the spirodiamines and gas chromatography. (c) 2005 Elsevier Ltd. All rights reserved.
Synthesis of enantiopure 5.7-spirodiamines: (S)-1,7-diaza[4.6]undecane and related compounds
摘要:
The efficient synthesis of enantiomerically pure (S)-1,7-diaza[4.6]undecane and (S)-7-methyl-1,7-diaza[4.6]undecane and related compounds is reported. These novel diamines are obtained from (S)-proline, which is reacted with chloral to give an enantiomerically pure oxazolidinone, which is alkylated at the alpha-position using cis-1,4-clibromobutene. The resulting allylbromide is then reacted with ammonia or methylamine to yield, as intermediates, allylamines, which ring close to give the corresponding spirolactams. The parent and the 7-methyl (S)-5.7-spirodiamines are obtained via reduction in two steps of the spirolactams. The expected absolute configuration was confirmed by X-ray structural analysis. Enantiomeric excess (> 99.8% ee) was determined using the Mosher amides of the spirodiamines and gas chromatography. (c) 2005 Elsevier Ltd. All rights reserved.